Electric heating device.



PATENTED JUNE 26, 1906. YOUNG.

I. GRETTUM & 0. L

ELECTRIC HEATING DEVICE.

APPLICATION FILED AUG. 31 1905.

FIG. 3

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ELECTRIC HEATING DEVICE,

Specification of Letters Patent.

Patented June 26, 1906.

Application filed August 31, 1905. $erial No. 276.604.

To all whom it may concern.-

Be it'known that we, INGEBRIGT GRETTUM and OSCAR L. YOUNG, citizens of the United States, residing at Duluth, in the county of St. Louis and State of Minnesota, have invented certain new and useful Improvements in Electric Heating Devices, of which the following is a specification.

Our invention relates to improvements in electric heating devices, and refers particularly to a device of this character adapted for use in the generation-of steam or for use in any place where hot water or steam is required. i

The main object of our invention is the provision of a device of the character described which may be connected with any suitable source of electric power and which will rapidly heat the Water to the required degree or generatelsteam and which will be efiicient and practical in every particular.

Another object of our invention is the provision of an electric heating devicewhich may be applied to an ordinary tubular boiler and which will form a simple, clean, and eflicient means for heating the Water or generating the steam.

With these objects in view our invention consists of a boiler provided with a series of flues, conductors secured in said flues and in- 3 represents a longitudinal central sectional view of one of the insulating-tubes with the conductor therein.

The letter A designates on ordinary tubular boiler, which is supplied with the usual in let and outlet connections H and K, respectively, and is provided with the flues B. In these flues are inserted insulating-tubes O, which are of a materialfnot readily affected by heat, such as mica or other suitable insulation. In this insulating-tube a refractory conductor D is placed and is provided at the ends with terminal lugs E, having bindingscrews F therein, adapted to secure the wires G, which are connected at one endwith a suitable source of electric power and at the other end are provided with individual switches. It will be seen that any desired number of the conductors may be cut into or out of circuit by the operation of these switches, and thus the degree of heat may be regulated at Will. At the ends of the conductors are secured insulating-bushings or coveringplates L, which make an air-tight joint with the boiler and hermetically seal the boilervflues, and thus prevent the heat from radiating from said flues. The conductors may be of any suitable refractory conducting material, such as carbon, and they may be in a solid piece, as shown, or they may be cut in blocks and inserted in the insulating-tube.

From this description, taken in connection with the drawings, it will be clearly seen that we rovide an electric heating apparatus whic is simple and durable in construction, which can be produced and operated at a low cost, and which will be very useful for heating purposes and for the generation of steam.

We claim 1. The combination with a boiler provided with suitable flues, of carbon conductors within said flues, insulating-tubes surrounding the conductors, covering-plates on the ends of the conductors, and terminal lugs having threaded ends engaging the conductors, and provided with longitudinal slots and set-screws to secure the wire therein, said lugs serving to secure the cover-plates in position.

2. In combination with a boiler having suitable flues therein, carbon conductors inclosed in insulating-tubes disposed within the flues, insulating-caps on the ends of the conductors making air-tight joint with the flues,

lugs screwed in the ends of the conductors to secure the caps in place, said lugs having longitudinal openings and set-screws to secure the Wire therein.

In testimony whereof we afliX our signatures in presence of two witnesses.

INGEBRIGT GRETTUM. OSCAR L. YOUNG.

Witnesses:

- E. H. HALL,

HAZEL PORTERFIELD.

IOO 

